Also, I understand that Gethsemene belonged to Sint before OG.
This is wrong. When Sint was founded in Fianik, OG's northern/northeastern borders were Fikman and Haji. So yes, in 2005 OG had Gethsemene and maintained that control until late-ish 2007 when the Daimons invaded and drove OG's northeastern regions rogue, letting their allies in Sint take the lands without getting their hands dirty.
http://www.youtube.com/watch?v=DCqxoaZx7qY&feature=youtu.beProof if you need it, actually.